endioott



2 Sheets-Sheet .1.

(No Model.)

MVT", ENDICO'IT. DRY DOCK.

Patented Mar. 15, 1892.

15:06 Him? ail'izsse s,

2 sheets sheet 2.

[72 maul 07.

O O QOYOVOYO'Q O Patented Mar. 15, 1892-.

DRY DOCK.

flyf 0 4 0 M. T. B'NDIGOTT.

z Lnes es L e d 0 M 0 N UNIT STATES ATE T FFICE.

MORDECAI T. ENDICOTT, OF WVASHINGTON, DISTRICT OF COLUMBIA.

DRY-DOCK.

SPECIFICATION forming part of Letters Patent N 0. 470,750, dated March15, 1892.

Application filed August 28, 1891. Serial No. 404,014. (No model.)

To all whom it may concern:

Be it known that I, MORDEOAI T. ENDICOTT,

I of Washington, in the District of Columbia,

have invented certain new and useful Improvements in Dry-Docks; and I dohereby declare the following to be a full, clear, and exactspecification of the same.

My invention relates to improvements in the construction of permanentdry-docks, wherein vessels are built or repaired,\vl1ich are locatednear or on the margins of water-ways or harbors; and the object of myinvention is the improvement of the construction, so as to renderdry-docks stronger and more durable.

To accomplish the above results the invention consists of certain novelfeatures of construction and detail and certain combinations andarrangements of parts herein described, and further illustrated in theaccompanying drawings, which form a part of this specification.

In the'drawings, Figure l is a transverse section of one-half of adry-dock constructed according to my invention. Fig. 2 is an enlargedview of a portion of one side shown in Fig. 1. Fig. 3 is a cross-sectionof a piece of timber from which the altars or steps forming the interiorlining in part are formed. Fig. 4 is a cross-section of apart of thedock, showing the sub-drains. Fig. 5 is a plan view showing thearrangement of the sub-drains under-V neath the concrete, and Fig. 6 isa detail transverse section showing the connection of the sub-drainswith the culvert or drain leading to the pump-well.

Similar letters refer to similar parts throughout the several views.

In the construction of a dock in accordance with my present invention,where the material underlying the tloor of the dock is yielding,foundation-piles E E are driven over the area of the floor and out offat the proper level, and on the tops of these piles are securedlongitudinal timbers H IL The soil around the heads of the said .pilesis excavated to the desired depth and longitudinal perforated or porousdrains D D, of wood, iron, earthenware, stone, or any other suitablematerial of any convenient or desired cross-section or shape, are thenlaid over the area, as many as are desired, intersecting similartransverse drains D D, extending outwardly as far as the row ofsheet-piling F. A mass of concrete I I is then rammed in the spaceexcavated, covering the drains D D and D D, and longitudinaldrainage-culverts D D are formed where desired, preferably in the centerof each half of the dock or at the sides near the altars. Transversejoists B B are then laid on and secured to the longitudinal timbers H H.Another layer of concrete is then rammed upon that previously laid tothe tops of the transverse joists B B at the lowest altar and toone-half the height of the same at the center of the dock along thekeelway and sloping from these points to the drainage-culverts I) D Thelongitudinal drainsD D are extended to and connect with a much largercrossdrain leading to the sump or well. The longitudinal drains D D andthe transverse drains D D intersect and connect with each other, thusforming a net-work and system of sub-drains underlying the entirefloorarea and conveying the sub-drainage to the aforesaid sump or Well,whence it is pumped and discharged into the water-way or harbor,

thus relieving the floor of the dock and the base of the altar systemwithin the sheet-piling F from the hydrostatic pressure of the waterunderneath, tending to force it np,rupture it, or cause leaks. It alsoavoids the use of the vertical relief-valves along the culverts usuallyemployed, and horizontal flap-valves on the sides employed to relievethe hydrostatic pressure also, all of which are local in theiroperation, and generally choke up and fail to afford the relief andbenefit intended. The said relief-valves and flap-valves can, however,be used in the same dock with the sub-drains, as proposed, if desired.

The proposed combination and arrangement in a dry-dock of a system offoundation-piles, longitudinal timbers, and transverse joists filled inwith concrete having a net-work or a system of sub drains underneath torelieve the concrete and floor from the upward hydrostatic pressure ofthe spring and other waters, with a drainage culvert or area above underthe wooden-floor surface for the passage of the surface water, isintended to avoid the injurious and sometimes disastrous effects of theunequal and greater upward pressure underneath and thedisintegratingeffects and cavities caused by continued leaks from below or by thepassage upward to the deck of the water through pipes, and therebyincrease the stability and durability of the part of the dry-dockafliected and render the floor and lower parts of the altar system drierand in better condition for use in the repair and construction ofvessels. The same system of sub-drains may be used where no piles aredriven in the bottom and the floor and loads are sustained by the layerof concrete resting upon a firm stratum of earth or rock.

The sides of the dry-dock are constructed by securing the inclinedtimbers Ato the heads of the inclined brace piles G, previously driven,also to the cap-timbers and piles at the top and the transverse joist Bat the bottom, all as shown, and then securing to the inclined timbersor altar-carriages A the altars C 0 The space back of the altars maythen be filled to any desired depth with clay puddle, concrete, or anyother suitable material.

The object in driving the piles G G at an angle with the vertical is tobring the center line or direction of these piles nearer to thedirection of the strains upon them, whether from the thrust of shoresfrom a vessel, or from the thrust of the embankment in the rear, or fromthe hydrostatic pressure of water in the rear or in the front when thedrydock is full of water.

The piles driven at an angle with the vertical, which may vary from theangle shown, will resist all these strains much more effectively thanwhen driven vertically, and therefore renders the d ry-dock moresubstantial and the side construction less liable to failure ordistortion and resultant leakage. .According to my plan thecorresponding piles in the sides of the entrance and abutments aredriven in the same manner at any angle from the ver- .tical.

The altars O C are shown more clearly in Figs. 2 and 3. In the latterthe timber K L M O P is one from which the altar K L N O P is sawed. Theline L N is the line of cut, bisecting the side K M at L, and is sawedat the same angle with that side that the altarcarriage A in Figs. 1 and2 makes with the vertical. The two triangles .I L K and M L N are thenalways equal, and the piece L M N, cut from the timber, when revolvedthrough one hundred and eighty degrees about the apex L, occupies theposition J L K in Fig. 3, corresponding with its position J L K in Fig.2, which shows it filling exactly the space in the rear of the altar 0when the latter is secured to the altar-carriage A in itsproperposition, and which piece (marked 0 when secured forms acarriage-block for the altar next above which rests upon it and alsooverlaps it, resting partly upon the main altar below. The pieces thussawed off from the timber maybe cut into short lengths to formcarriage-blocks to fill only the space immediately between the largealtar-timbers C and the inclined brace-timbers or altar-carriages A, orthey may be laid forming continuous lengths behind the large altars 0,thus increasing the dimensions and strength of the altar system toresist the hydrostatic pressure from either face, the thrust from theearth behind and shores in front, and rendering it less liable toleakage.

If preferred, the altars C may be laid and secured, as shown, butdispensing with the pieces 0 and filling in the space with puddle,concrete, or other material. In my plan the lowest altar G, secured tothe transverse joists B and the altar-carriage A, from its shape anddimensions performing the duty of the ordinary stringer, is the base ofthe altar system and assists in securing the foot of the altar-carriagesA.

I am aware that sub-drains have been laid under masonry dry-docks, and Ido not claim any patent upon the same. My present claim is animprovementin timber dry-docks (which from their material and method ofconstruc tion need relief from the upward passage and pressure of thewater) by the application of a system of sub-drains to them, forming thecombination hereinbefore set forth.

I claim- 1. In a dry-dock, the inclined piles driven at an angle fromthe vertical, forming a part of the side structure of the dock,substantially as described.

2. In a dry-dock, the altars or steps 0 O of the form substantially asshown and arranged, the bottom of one to lap upon the next below andsecured to the altar-carriages A A.

3. In a dry-dock, the combination of the altars C C and the filling-intimbers C C, together forming the altar system and side lining,substantially as shown and arranged.

4. In a dry-dock, the longitudinal and low est altar (1 of the formshown resting partly upon the joist B and partly upon the altarcarriageA and secured to the said joist I3 and the said altar-carriage A andforming the base and a part of the altar system, the said altar C alsosecuring the foot of the altar-carriage A.

5. In a dry-dock, the combination of a botcom or floor constructedpartly of wood and partly of concrete with a system of transverse andlongitudinal drains underneath the concrete, conducting the sub-drainagewater to the well without its passing up through the bottom or floor, asand for the purposes described.

INDICOTT.

ICO

